1. Field of the Invention
The present invention relates to a pressure sensor for measuring a pressure by a sensor chip responsive to the pressure.
2. Discussion of the Related Art
Heretofore, in pressure sensors of an oil filled type having a metal diaphragm, one described for example in the following patent document 1 has been known, wherein an insulating member made of alumina-based ceramics is provided between a joint housing made of a copper-base alloy having a mounting section onto a pressure measured device and a sensor housing made of stainless steel for electrically insulating the joint housing and the sensor housing from each other.                [Patent Document 1]: Japanese Unexamined, Published Patent Application No. 2004-37318 (Paras. 0015 and 0030, FIGS. 1 and 2)        
The prior art pressure sensor as aforementioned is accompanied by the problem that it is liable to suffer the influence of electrical noise from outside since a signal line of the pressure sensor and the sensor housing are electrically suspended or unfixed.